Years of international negotiations to resolve the Iranian nuclear crisis have reached a crucial moment, with a deadline set for Tuesday night. The outcome will be critical for Iran, which could have tough sanctions lifted - or tightened. Here, ordinary Iranians tell the BBC's Persian service about their hopes and fears over the talks.
Arash, from Isfahan
I own a mobile phone shop. Every positive or negative news from the nuclear talks affects exchange rates and prices.
The market is already very quiet as people don't have enough money to spend.
If the nuclear talks fail, the exchange rates and prices will increase and I might lose my business as people cannot buy anything.
Mohammad, from a location in Iran
I am a contractor in a national petrochemical plant. I am optimistic that they can obtain the agreement so investors can come to Iran and invest in the oil and petrochemical industry.
[Sanctions mean] we have not been able to purchase necessary spare parts, and that has had a wide range of negative effects on our production.
Laleh, living in Germany
As an Iranian I thank Mr [Barack] Obama and [US Secretary of State] [John] Kerry because in spite of all the pressure from Israel and the [US] Senate's Republicans, they are still doing their best to reach to an agreement.
I believe the West now acknowledges Iran's power in the Middle East and they want to get to a conclusion this time.
Aziz, from Tehran
I own a chemical additive factory. Sanctions caused lots of problems for our business. For example, in the past 10 years we could not export our products and we lost our overseas market.
I hope nuclear talks are successful and the West lifts the sanctions as soon as possible.
Mehran, from Tehran
The West cannot lift the sanctions at once as they need a guarantee from Iran while Iran has showed it is not reliable.
By the way [Iranian Foreign Minister] Mr [Mohammad Javad] Zarif is doing his best to reach an agreement as he knows sanctions destroyed the economy in Iran.
Kourosh, from Tehran
I don't think we can reach an agreement. The US need to show their goodwill.
They propose a step-by-step agreement to lift the sanctions gradually, though it's not clear who has to take the first step.
Jalil, living in the US
I'm so optimistic about reaching an agreement.
Seeing Iran and the US negotiating the details directly shows that both sides are serious about getting to an agreement.
I also believe that the majority of American people also support Obama's policy towards Iran's nuclear programme.